45-45-90 Special Right Triangle

45-45-90 Triangles
A 45-45-90 triangle is a special type of isosceles right triangle where the two legs are congruent to one another and the non-right angles are both equal to 45 degrees. Many times, we can use the Pythagorean theorem to find the missing legs or hypotenuse of 45-45-90 triangles. The ratio of the sides to the hypotenuse is always 1:1:square root of two.

Introduction to 45-45-90 Triangles

Special Right Triangles (45-45-90)
This video explains in more detail about the 45-45-90 special right triangle. It also solves 3 different 45-45-90 right triangle problems that you will come across in your geometry class.

Solve a 45-45 Right Triangle
This video provides examples of how to solve a 45-45-90 triangle given the length of one side.

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